US4535034A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High Al heat-resistant alloy steels having Al coating thereon
Assignee: Nippon Steel Corp
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Filing: 1983-12-30
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Granted: 1985-08-13
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Expires: 2003-12-30
Abstract
Abstract A high-Al heat resistant steel comprising a base steel containing not more than 0.7% C, not more than 3.0% Si, not more than 2.0% Mn, 10 to 40% Ni, 9 to 30% Cr, 2 to 8% Al, with balance being Fe and unavoidable impurities, and an Al coating formed on the base steel. The Al coating diffuses into the base steel to form an intermediate Al alloyed layer during the Al coating or by heating after the coating, which alloyed layer prevents the Al coating from spalling, thus providing excellent resistance to oxidation, corrosion, carburization, nitrization and sulphurdization at elevated temperatures.
Inventors
- 👤 Takashi Zaizen
- 👤 Yasuo Otoguro
- 👤 Mikio Yamanaka
- 👤 Shozo Yamane
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 14:16
CPC Classifications
C; C23; C23C; C23C30/00; B; B32; B32B; B32B15/00; B32B15/01; B32B15/012; C23C10/00; C23C10/28; Y; Y10; Y10T; Y10T428/00; Y10T428/12; Y10T428/12493; Y10T428/12736; Y10T428/1275; Y10T428/12757; Y10T428/12771; Y10T428/12861; Y10T428/12951
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
59 words
A high-Al heat resistant coated steel comprising a base steel consisting essentially of, in weight percent, not more than 0.7% C, not more than 3.0% Si, not more than 2.0% Mn, 10 to 40% Ni, 9 to 30% Cr, 2 to 8% Al, with balance being Fe and unavoidable impurities, and an Al coating formed on the base steel.
Claim 2
Dependent Claim
59 words
A high-Al heat resistant coated steel comprising a base steel consisting essentially of, in weight percent, not more than 0.7% C, not more than 3.0% Si, not more than 2.0% Mn, 10 to 40% Ni, 9 to 30% Cr, 2 to 8% Al, with balance being Fe and unavoidable impurities, and an Al coating formed on the base steel.
Claim 3
Dependent Claim
60 words
A high-Al heat resistant coated steel comprising a base steel consisting essentially of, in weight percent, not more than 0.7% C, not more than 3.0% Si, not more than 2.0% Mn, 10 to 40% Ni, 9 to 30% Cr, 2 to 8% Al, with balance being Fe and unavoidable impurities, and a high-Al alloy layer formed on the base steel.
Claim 4
Dependent Claim
60 words
A high-Al heat resistant coated steel comprising a base steel consisting essentially of, in weight percent, not more than 0.7% C, not more than 3.0% Si, not more than 2.0% Mn, 10 to 40% Ni, 9 to 30% Cr, 2 to 8% Al, with balance being Fe and unavoidable impurities, and a high-Al alloy layer formed on the base steel.
Claim 5
Dependent Claim
23 words
A high-Al heat resistant coated steel according to claim 1, in which the Al coating is formed by an Al hot dipping process.
Claim 6
Dependent Claim
21 words
A high-Al heat resistant coated steel according to claim 1, in which the aluminum is formed by an electro-aluminum plating process.
Claim 7
Dependent Claim
21 words
A high-Al heat resistant coated steel according to claim 1, in which the aluminum coating is formed by a calorizing process.
Claim 8
Dependent Claim
21 words
A high-Al heat resistant coated steel according to claim 1, in which the aluminum coating is formed by a metallizing process.
Claim 9
Dependent Claim
37 words
A high-Al heat resistant coated steel according to claim 2, in which the high Al alloy coating is formed by heating the high-Al heat resistant steel with the Al coating thereon at a temperature above 500° C.
Claim 10
Dependent Claim
22 words
A high-Al heat resistant coated steel according to claim 1, in which the Al coating is 1 to 500 μm in thickness.
Claim 11
Dependent Claim
22 words
A high-Al heat resistant coated steel according to claim 1, in which the Al coating is partially alloyed with the base steel.
Claim 12
Dependent Claim
39 words
A high-Al heat resistant coated steel according to claim 1 wherein the base steel has the composition 0.078% C, 0.53% Si, 1.54% Mn, 23.2% Ni, 22.4% Cr, 2.10% Al, 0.3% Ti with the balance being Fe and unavoidable impurities.
Claim 13
Dependent Claim
41 words
A high-Al heat resistant coated steel according to claim 1 wherein the base steel has the composition 0.15% C, 0.63% Si, 0.74% Mn, 35.3% Ni, 12.0% Cr, 6.79% Al, 0.79% Mo, 0.05% Ce with the balance being Fe and unavoidable impurities.
Claim 14
Dependent Claim
43 words
A high-Al heat resistant coated steel according to claim 1 wherein the base steel has the composition 0.45% C, 1.07% Si, 0.53% Mn, 28.3% Ni, 15.2% Cr, 7.58% Al, 0.05% Ce, 0.01% La, 0.001% Ca with the balance being Fe and unavoidable impurities.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-08-12 | 1989-02-11 | 1989-08-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-08-12 | 1993-02-11 | 1993-08-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-08-12 | 1997-02-11 | 1997-08-13 | $7700.00 | Window Closed / Lapsed |